This year our group, often in collaboration with others, published six primary studies related to DNA replication fidelity. We showed that DNA polymerase delta stalls when replicating telomeric DNA sequences. Surprisingly compared to expectations from the current literature, this stalling occurs independent of formation of G-quadruplexes in DNA. In collaboration with R. Scott Williams group, we showed that aprataxin resolves adenylated RNA-DNA junctions to maintain genome integrity. In collaboration with L.C. Pedersen, we performed a structure-function analysis of ribonucleotide bypass by B family DNA replicases. We also continued to collaborate with Dr. Pedersen, and added a new collaboration with M. Garcia-Diaz, to perform three novel structure-function studies of Family X DNA polymerases lambda and mu that participate in repairing DNA damage resulting from physical and chemical environmental stressors. In addition, we published a methodology article, two review articles and an article highlighting a major breakthrough in DNA replication enzymology.